The present invention relates generally to the electrokinetic mass transfer of substances into and/or extracting substances from tissue and particularly to apparatus and methods for extracting, e.g., body fluids and/or harmful substances from a site, and/or delivering substances, e.g., a medicament to a treatment site.
Electrokinetic delivery of medicaments for applying medication locally through an individual""s skin is known. One type of electrokinetic delivery mechanism is iontophoresis, i.e., the application of an electric field to the skin to enhance the skin""s permeability and to deliver various ionic agents, e.g., ions of soluble salts or other drugs. In certain situations, iontophoretic transdermal or transmucocutaneous delivery techniques have obviated the need for hypodermic injection for many medicaments, thereby eliminating the concomitant problem of trauma, pain and risk of infection to the individual. Other types of electrokinetic delivery mechanisms include electroosmosis, electroporation, electromigration, electrophoresis and endosmose, any or all of which are generally known as electrotransport, electromolecular transport or iontophoretic methods. The electrokinetic delivery mechanism may also be accompanied by ultrasonic vibration to further facilitate electrokinetic transport of the substance, e.g., by opening pathways in the skin. Ultrasound may be employed in a number of ways such as (i) traditional piezoelectric elements, (ii) magnetostrictive alloys, (iii) Application Specific Integrated Circuits (ASICS) with an ultrasound transmitter built in or (iv) by thin foil sheets with incorporated piezoelectric dipole elements. See, for example, U.S. patent application Ser. No. 09/205,751, filed Dec. 4, 1998, of common assignee herewith, the disclosure of which is incorporated herein by reference.
There are several difficulties with electrokinetic delivery of substances such as medicaments. One is the heretofore need for somewhat cumbersome, bulky and costly equipment which oftentimes requires the presence of an individual at a doctor""s office or treatment center and use of medical professionals to administer the medicament. Private, self-administration of medicaments or for diagnostic application by the individual at non-medical or non-professional facilities is highly desirable. Also, an easily transportable apparatus for electrokinetic delivery of medication, for example, a lightweight, compact portable device useful with an applicator packaged as a single or unit dosage applicator, and which may be readily and easily manipulated to contact the treatment site appears ideal as a patient/consumer friendly self-administration system appropriate for many circumstances.
In accordance with a preferred embodiment of the present invention, there is provided a portable, self-contained, digit-mounted, lightweight, compact and wireless electrokinetic device or medicator for delivering a substance, e.g., a medicament, for self-administration to a treatment site. By the term substance is meant a medicament as well as natural or homeopathic products that may be outside the definition of medicament, e.g., inks and pigments for tattoos, and more generally includes any substance capable of electrokinetic transport through skin or mucocutaneous membrane, e.g., into a treatment site or from a site, e.g., for diagnostic purposes. The majority of applications using the present invention are for applying medicaments to treatment sites and therefore the terms medicament and substance are used interchangeably, each embracing the other, the term medicament being used in lieu of the term substance throughout this specification for convenience. By medicament is meant any chemical or biologic substance that may be used on or administered to humans or animals as an aid in the diagnosis, treatment or prevention of disease or other abnormal or cosmetic condition or for the relief of pain or to control, diagnose, measure, detoxify or improve any physiologic or pathologic condition. By a treatment site is meant a target tissue, e.g., a diseased tissue, or diagnostic/detoxification site for extraction of a substance, underlying or exposed through or on an individual""s skin, cutaneous or mucocutaneous membrane.
In a first aspect of the present invention, an individual may privately self-administer the medicament by employing the self-powered wireless finger-mounted device hereof to electrokinetically drive the medicament into the treatment site, e.g., through the skin or mucocutaneous membrane to a diseased tissue. Preferably, a low-cost digit-mounted device is used to facilitate the flow of medicament into the skin under the influence of the electromotive force supplied to the medicament by the self-powered digit-mounted wireless device. The device is preferably lightweight, compact, inexpensive and portable and comprises a device body or splint configured for mounting on an individual""s extremity for self-manipulation and containing a power source, for example, a battery, connected directly or indirectly to first and second terminals and suitable electronics controlling and interfacing with active and counter electrodes. The device is preferably mounted on the individual""s finger to facilitate manipulation of the device so that the active electrode connected to the first terminal may be located against the skin or mucocutaneous membrane, i.e., the treatment site. The second terminal of the power source is coupled with the counter electrode, i.e., a tactile electrode, on the surface of the device for electrical contact with a second skin site, e.g., a portion of the individual""s finger engaged by the device. The polarity of the active and counter electrodes may be reversed by either a mechanical switch, a relay or solid-state implementation as the application may dictate. By self-manipulation is meant that the individual can mount the device on a finger of one hand or a portion thereof and substantially freely orient the device to engage the active electrode of the device through a substrate containing medicament or a conductive carrier therefor, or directly through medicament interposed between the skin or mucocutaneous membrane and the active electrode, generally wherever the treatment site is located and irrespective of whether a substrate is used and, if used, irrespective of whether the substrate is attached to the device or to the individual""s skin or mucocutaneous membrane or interposed therebetween with the device subsequently applied to the substrate.
In a preferred embodiment of the present electrokinetic medicament delivery device, there is provided a substrate having an open cellular structure, for containing the medicament. This preferred open cellular or porous substrate forms a minimum barrier to movement of medicament molecules under the influence of the applied current to electrokinetically transport the medicament molecules into the skin or mucocutaneous membrane. The substrate is preferably pre-filled with a single or unit dose of medicament and pre-packaged with or in an applicator portion of the device prior to application of the device and the attached substrate to the treatment site. It will be appreciated, however, that the substrate can be applied directly to the treatment site or form a substrate interposed between the device, i.e., the active electrode and the treatment site without attachment to the device. For those medicaments which are not per se iontophoretically transportable, the medicament and/or the substrate may be hydrated prior to use or contain a hydrating substance, e.g., water, in prepackaged form containing both the medicament and hydration substance. The hydration substance may contain salts or other ionizable ingredients and is therefore conductive to facilitate electrokinetic transport.
It will be appreciated that upon application of the substrate to the treatment site with the medicament interposed between the active electrode and treatment site, an electrical circuit is completed through the active electrode of the device, the medicament or hydrated medicament in the substrate and the treatment site for return through the individual""s skin in electrical contact with the counter electrode of the device. Thus, with the device carried, for example, by the individual""s finger in contact with the counter electrode carried by the device, an electrical circuit is completed from the device through the active electrode, the medicament or hydrated medicament, the treatment site, the individual""s torso, arm, hand and the tactile electrode. To facilitate completion of the electrical circuit, either or both electrodes may contain or have an overlying layer of an electrically conductive material, for example, hydrogel.
In a preferred embodiment of the present invention, the electrokinetic device is provided in the form of an electrokinetic finger splint medicator, which may be either disposable or reusable or have multiple parts with one part disposable and another part reusable. Preferably, the medicator is releasably secured to the finger of an individual and is preferably provided in two parts: a distal portion mounting an applicator head and a proximal portion mounting a housing for electronics and a power source. The two parts are preferably releasably secured to one another at the time of use. The proximal part contains, inter alia, a power source, various electronics for providing the appropriate electrical current necessary to electrokinetically drive the medicament into the treatment site, finger-mounting securing elements, and electrical contacts. In the preferred embodiment, the proximal part is preferably reusable and may be in either a durable long-term use format or of a more limited time and/or number of uses format, e.g., one year and/or some pre-set, limited number of uses, e.g., five uses, before becoming inoperable, referred to herein as a reposable portion. However it will also be appreciated that the proximal portion may be non-reusable and disposable after only one use. The distal portion preferably carries the active electrode at a location along the outermost end portion of the distal portion and facing outwardly thereof. The substrate containing medicament lies in contact with the active electrode and its opposite planar surface extends at an oblique angle from the underside of the distal portion to facilitate engagement with the treatment site. The counter electrode preferably extends along an inside surface of the distal portion, i.e., opposite the fingerprint portion of the individual""s finger respectively. Alternatively or conjunctively, the counter electrode may be located along the underside of the proximal portion. In either case, the counter electrode electrically connects the power source and the individual""s finger. When the proximal and distal portions of the medicator are secured to one another, electrical contacts on the proximal and distal portions are electrically connected with one another thus placing the active electrode on the distal portion in electrical contact with the power source and electronics contained in the proximal portion. The counter electrode is also electrically connected with the power source upon securing the distal and proximal portions to one another. Alternatively, an on/off switch may be provided in the electrical circuit whereby, upon securing the distal and proximal portions to one another, the on/off switch may be subsequently switched from the off position to the on position to activate the circuit.
The power source and electronics are preferably carried by and along outermost portions of the proximal portion. The proximal portion is shaped and configured to lie along the finger preferably just forward of the individual""s knuckle joint and may extend further back along the back side of the hand. One or more elements for securing the proximal portion to the individual""s finger are provided. For example, straps having hook-and-loop fasteners (Velcro(copyright)) are preferably provided to secure the medicator proximally to the individual""s fingertip. Alternately, as a further example a soft malleable metal arm or arms may be employed to secure the device to the digit. When the distal and proximal portions are secured to one another, the tip of the individual""s finger preferably overlies the counter electrode opposite the active electrode.
Preferably, the distal portion has a ring-like or annular configuration for receiving the tip of the individual""s finger, the active electrode being housed in an applicator head underlying and electrically insulated from the fingertip or fingerprint portion of the individual""s finger. Thus, the active electrode is located in a support or housing carried by the distal portion and has an exposed surface for electrical contact in a separate substrate with (i) a medicament disposed in a porous substrate within or attached to the housing, (ii) medicament in a substrate interposed between the active electrode and the treatment site or (iii) with the medicament per se. With the medicament disposed in a substrate, e.g., a porous pad, applied, fitted or urged into electrical contact with the active electrode or with the medicament applied directly on the active electrode or the treatment site, it will be appreciated that the active electrode of the finger splint medicator can be readily and easily manipulated to engage the medicament, and hydration material if necessary, or substrate carrying the medicament interposed between the active electrode on the medicator against the treatment site.
In accordance with one aspect of the present invention, an electrokinetic delivery system for personal use in self-administration of a medicament to a treatment site on an individual includes a device for releasable securement to an individual""s finger and shaped in part to conform to at least a portion of the individual""s finger. A retainer releasably secures the device to the individual""s finger and a self-contained power source is carried by the device. First and second electrodes are carried by the device. The first electrode is in electrical contact with the power source and is adjacent a distal end portion of the device and adjacent the tip of the individual""s finger upon retention of the device on the individual""s finger. The second electrode is for electrical contact with a portion of the individual""s body and is in electrical contact with the power source. Upon application of the first electrode to a treatment site with the medicament interposed between the first electrode and the treatment site and completion of an electrical circuit through the first electrode, the medicament or conductive carrier therefor, the treatment site, the individual""s body, the second electrode and the power source, the device causes an electrical current to flow for electrokinetically driving the medicament into the treatment site.
In accordance with another aspect of the present invention, an electrokinetic delivery system for personal use in self-administration of a medicament to a treatment site on an individual includes a device having a generally ring-shaped body and a through-opening for receiving and releasably retaining the device on the finger of the individual. The device further includes a self-contained power source carried by the device, a first electrode in electrical contact with the power source, and a second electrode for electrical contact with a portion of the individual""s body. The second electrode is in electrical contact with the power source. Upon application of the first electrode to a treatment site with the medicament interposed between the first electrode and the treatment site and completion of an electrical circuit through the first electrode, the medicament or conductive carrier therefor, the treatment site, the individual""s body, the second electrode and the power source, the device causes an electrical current to flow for electrokinetically driving the medicament into the treatment site.
In accordance with yet another aspect of the present invention, electrokinetic self-administration of a medicament into a treatment site for an individual is provided by: providing a device shaped in part to conform to at least a portion of an individual""s finger and having a self-contained power source, first and second electrodes, and a substrate in electrical contact with said first electrode and including an electrokinetically transportable medicament and an exposed contact surface; releasably retaining the device on the individual""s finger, with the second electrode in electrical contact with the individual""s finger; while the device remains retained on the individual""s finger, placing the contact surface of said substrate into contact with the individual""s treatment site; and causing electrical current to flow through said first electrode, the medicament or a conductive carrier therefor, the treatment site, the individual""s body, said second electrode and said power source to electrokinetically drive the medicament into the treatment site.
In a preferred embodiment according to the present invention, there is provided an electrokinetic delivery system for personal use in self-administration of a medicament to a treatment site on an individual, comprising a device for releasable securement to an individual""s finger and shaped in part to conform to at least a portion of the individual""s finger, a retainer for releasably securing the device to the individual""s finger, a self-contained power source carried by the device, a first electrode carried by the device adjacent a distal end portion thereof and adjacent the tip of the individual""s finger upon retention of the device on the individual""s finger, the first electrode being in electrical contact with the power source, a second electrode carried by the device for electrical contact with a portion of the individual""s body, the second electrode being in electrical contact with the power source whereby, upon application of the first electrode to a treatment site with the medicament interposed between the first electrode and the treatment site and completion of an electrical circuit through the first electrode, the medicament or conductive carrier therefor, the treatment site, the individual""s body, the second electrode and the power source, the device causes an electrical current to flow for electrokinetically driving the medicament into the treatment site.
In a further preferred embodiment according to the present invention, there is provided an electrokinetic delivery system for personal use in self-administration of a medicament to a treatment site on an individual, comprising a device having a generally ring-shaped body and a through-opening for receiving and releasably retaining the device on the finger of the individual, a self-contained power source carried by the device, a first electrode carried by the device in electrical contact with the power source, a second electrode carried by the device for electrical contact with a portion of the individual""s body, the second electrode being in electrical contact with the power source whereby, upon application of the first electrode to a treatment site with the medicament interposed between the first electrode and the treatment site and completion of an electrical circuit through the first electrode, the medicament or conductive carrier therefor, the treatment site, the individual""s body, the second electrode and the power source, the device causes an electrical current to flow for electrokinetically driving the medicament into the treatment site.
In a further preferred embodiment according to the present invention, there is provided a method of treatment by electrokinetic self-administration of a medicament into a treatment site for an individual, comprising providing a device shaped in part to conform to at least a portion of an individual""s finger and having a self-contained power source, first and second electrodes, and a substrate in electrical contact with the first electrode and including an electrokinetically transportable medicament and an exposed contact surface, releasably retaining the device on the individual""s finger, with the second electrode in electrical contact with the individual""s finger, while the device remains retained on the individual""s finger, placing the contact surface of the substrate into contact with the individual""s treatment site and causing electrical current to flow through the first electrode, the medicament or a conductive carrier therefor, the treatment site, the individual""s body, the second electrode and the power source to electrokinetically drive the medicament into the treatment site.